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In this article, GPR – Ground Penetrating Radar and inductive electromagnetic (EM38 equipment) results are presented for three archaeological sites of shell mounds located between Laguna and Jaguaruna cities, mid-southern coast of Santa Catarina state, Brazil. The Jabuticabeira II, Santa Marta IV, and Encantada III sites were studied. These sites consist of carbonate shell mounds built by societies that inhabited this region during the pre-colonial period (7.5–1.3 ky BP). Geophysical responses obtained in these archaeological sites had allowed the identification of anomalous regions related to archaeological point targets as well as continuous targets, correlated to the shell mound's structure and buried geologic features. GPR numerical modelling studies were done in order to evaluate the performance of the GPR method in relation to materials found in that environment, besides helping interpretations of real results. The synthetic GPR model was a good match with real data obtained in the field. So, the real and synthetic results serve as a reference guide to direct excavation activities in these archaeological and geological structures. In the Jabuticabeira II shell mound, lithic materials and burials were found amidst archaeological layers characterized by sediment rich in organic material, ferruginous concretions, and loose shells. In the Santa Marta IV archaeological site, a concentration of ceramic materials, burials and fireplaces were found. In the Encantada III site, a strong anomaly characterized by a hyperbolic reflection was related to the presence of a silicified tree root; a great example of ambiguity in shallow geophysics interpretation in archaeological applications. Results functioned as a guide to archaeological excavations, allowing cost and time reduction as well as contributing to improve the knowledge of these archaeological sites situated in southern Brazil.  相似文献   
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We present results of electrical conductivity profiles obtained with inductive electromagnetic geophysical method in Santa Marta archaeological site, Santa Catarina State, southern Brazil. This site is a sambaqui (shell mound), in which several human occupation remains are found during pre-colonial period such as buried lithic and bone artifacts, fire-place, etc. Most of these mounds include as well many human burials, which, in many cases, point to funerary ritual as a main agency for mound building. A set of profiles of apparent electrical conductivity and magnetic susceptibility was acquired in two sites aiming the identification of geophysical anomalies with potential interest for excavation. To enhance conductivity data, we applied an effective procedure to remove topographical effects in the apparent conductivity measurements, which are rather conditioned by the presence of a variable water table depth or conductive sediment layer. A linear dependence among conductivity values and the site elevation provided a simple linear model to remove the influence of topography. Corrected electric conductivity maps substantially improved the definition of anomalies, many of them rather subtle in raw data images. Corrected maps also show a better adherence with magnetic susceptibility maps, both of them identifying archaeological structures of interest: a well-structured fire-place and a concentration of ceramic fragments.  相似文献   
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Neandertal skeletal remains are usually contaminated with modern human DNA derived from handling and washing of the specimens during excavation. Despite the fact that the distinct Neandertal haplotypes allow the design of specific primer pairs, for instance in most of the mitochondrial DNA (mtDNA) hypervariable region 1 (HVR1), the human contaminants can often outnumber the endogenous DNA, thus preventing a successful retrieval of Neandertal sequences. We have developed a novel PCR method, based on the use of blocking primers that preferentially bind to modern human contaminant DNA and block their amplification, and greatly improve the efficiency of Neandertal DNA retrieval. We tested the method in four El Sidrón Neandertal samples (two teeth and two bone fragments) with different contamination levels and taphonomic conditions, and we have been able to significantly increase the Neandertal yield from figures around 25.23% (5–69.6%) up to 90.18% (75.3–100%).  相似文献   
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The Italian debate on industrial districts suggests that local development can be based on small and medium-sized firms, provided they work in teams and are embedded in a local system of social relations. If the availability of local public goods complements the private supply of local specialized services and goods, Marshallian external economies are engendered. When inner social and economic relations boost the supply of local public goods, and are reproduced by the consistent economic behaviour of local (economic and political) agents, they become local factors of economic development, or, in other words, the district's social capital. These propositions are considered within a three-layered framework comprising structure, conduct and performance. The relations among these levels allow joint consideration of three different processes of economic selection: competitive, strategic, evolutionary. This complexity is necessary if the conditions that foster significant Marshallian external economies are to be represented correctly.  相似文献   
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This paper is aimed at determining the effects of the soil characterization on the seismic input to use for seismic assessment. Three different soil profiles have been assembled to represent the stratigraphies found through a proper experimental investigation, carefully described, and alternative seismic site response analyses have been performed. The surface spectra obtained from the seismic site response analysis (SRA) are very different from each other, thus evidencing the importance of carefully describing soil stratigraphy. Furthermore, the comparison among the surface records found for different return periods has shown a limited sensitivity of the SRA to the seismic intensity.  相似文献   
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This article examines neutral Switzerland's recognition policy towards the divided states of Korea and Vietnam. Drawing comparisons with other neutrals, notably Austria and Sweden, allows us to assess the credibility of neutrality in the Global Cold War. All three neutrals explicitly or implicitly aimed to reinforce their neutrality through the principle of universality, which entailed the recognition of all regimes, no matter their political couleur. Yet this principle was not applied consistently, but rather pragmatically. Until the beginning of the 1970s, Switzerland, as well as Austria and Sweden, favoured the Western-oriented over the Communist halves of Korea and Vietnam. Thereby, this article argues, they undermined the credibility of neutrality. They were, however, willing to take that risk, because they feared that the recognition of North Korea and North Vietnam could irritate the United States, and provoke East German claims for recognition, which was undesirable due to the Hallstein doctrine and West Germany's economic weight. It was only with the rise of the Third World as a political force, and the softening of the US position that the neutrals, which saw themselves in competition with each other for status and influence, eventually recognised North Korea and North Vietnam.  相似文献   
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